Gear box, seal, and cover arrangements

Abstract

A gearbox for a wind turbine has a bearing arrangement positioned on the downwind side of a first stage planet carrier at a single locus. The planet carrier has a portion extending radially inwards and axially downwind from the planet gears. Thus, the weight of the gearbox is supported between the two theoretical support points of the pair of back to back tapered roller bearings at the downwind side of the first stage planet carrier. A member of unitary construction comprising gearbox flange, input shaft and first stage planet carrier, which can be cast as one piece, reduces the weight of this part compared to previous designs having separate components.

The invention claimed is: 
     
       1. A gear box for a wind turbine generator, comprising:
 a flange; 
 an input shaft; and 
 a planetary gear set comprising at least one planet gear supported by a planet carrier, 
 wherein said input shaft, said flange and said planet carrier are a one-piece integrated unit and form a member having an input shaft region between a flange region and a planet carrier region, and wherein said planet carrier region extends radially inwards and axially downwind from said planet gears. 
 
     
     
       2. The gearbox of  claim 1 , further comprising:
 a non-rotating support component, wherein said non-rotating support component comprises a bearing arrangement located in a single locus along the longitudinal axis and arranged to provide support between said planet carrier region and said non-rotating support component, said gearbox having no further bearings on said member between said locus and said flange region. 
 
     
     
       3. The gearbox of  claim 2 , wherein:
 said single locus is at the radially and axially extended part of said planet carrier region. 
 
     
     
       4. The gearbox of  claim 2 , wherein:
 said bearing arrangement is arranged to at least partially restrict non-rotational movement between said member and said non-rotating support component. 
 
     
     
       5. The gearbox of  claim 4 , wherein:
 said non-rotational movement is at least one of relative radial movement, relative axial movement, and relative tilt movement between said input shaft and said non-rotating component. 
 
     
     
       6. The gearbox of  claim 2 , wherein:
 said bearing arrangement comprises a double tapered roller bearing. 
 
     
     
       7. The gearbox of  claim 2 , additionally comprising:
 a cover arrangement, comprising: 
 a cover configured to detachably engage with said non-rotating support component so as to be disposed around said input shaft and over a substantial part of said planetary gear set, 
 wherein said cover is comprised of at least two parts to allow detachment for a member selected from the group consisting of maintenance and inspection. 
 
     
     
       8. The gearbox of  claim 7 , wherein:
 said cover has an outer peripheral region for engagement to said non-rotating support component. 
 
     
     
       9. The gearbox of  claim 7 , wherein:
 said cover has an inner peripheral region for encircling said planet carrier region. 
 
     
     
       10. The gearbox of  claim 7 , further comprising:
 a sealing arrangement, comprising: 
 a seal located between said cover and said non-rotating support component, which, in use prevents exchange of materials between an inside and an outside of said gearbox. 
 
     
     
       11. A wind turbine, comprising:
 a gearbox for a wind turbine generator comprising a flange; an input shaft; and a planetary gear set including at least one planet gear supported by a planet carrier, wherein said input shaft, said flange and said planet carrier are a one-piece integrated unit and form a member having an input shaft region between a flange region and a planet carrier region, and wherein said planet carrier region extends radially inwards and axially downwind from said planet gears; and 
 a non-rotating support component, wherein said non-rotating support component comprises a bearing arrangement located in a single locus along the longitudinal axis and arranged to provide support between said planet carrier region and said non-rotating support component, said gearbox having no further bearings on said member between said locus and said flange region. 
 
     
     
       12. The wind turbine according to  claim 11 , further comprising:
 a cover arrangement, comprising: 
 a cover configured to detachably engage with said non-rotating support component so as to be disposed around said input shaft and over a substantial part of said planetary gear set, 
 wherein said cover is comprised of at least two parts to allow detachment for a member selected from the group consisting of maintenance and inspection. 
 
     
     
       13. The wind turbine according to  claim 12 , further comprising:
 a sealing arrangement, comprising: 
 a seal located between said cover and said non-rotating support component, which, in use prevents exchange of materials between an inside and an outside of the gearbox.